Currently, more and more old people or babies or enabled man or patients cannot move by themselves. They must be carried by wheelchairs. Sometimes, people uses carts (or wagons) to transfer pets or goods, while theses works need to apply manpower to wheelchairs, carts, or wagons. Since great manpower needs to drive the wheelchairs, carts, or wagons, the moving ranges of these vehicles are confined to be nearby of the driving people. A frequent event is to transfer the old people to a park for sunny. The servant will feel ill at ease due to a great power being applied, but the wheelchair only be moved within finite ranges.
Therefore, there is an eager demand for a novel design which can improve above mentioned defects.